The Department of Health (DH) has drawn public attention to a field
safety advisory message relayed by the United Kingdom Medicines and
Healthcare Products Regulatory Agency concerning the Cameron Health
SQ-RX Pulse Generator (Model Number 1010), after the manufacturer
found that a limited subset of SQ-RX Pulse Generators may enter an
unexpected state under specific conditions, causing the device to
reset repeatedly and render therapy unavailable. The Pulse
Generator is a component of the Cameron Health S-ICD System, which
is an implantable cardioverter-defibrillator prescribed for
patients when cardiac arrhythmia management is warranted. According
to the advisory, which was spotted via DH's regular surveillance,
the medical device manufacturer Cameron Health, Inc. (Cameron
Health) has confirmed one occurrence when a device entered the
unexpected reset state and continuously emitted a series of audible
tones. The patient concerned alerted the physician and the device
was replaced without further complications. Further investigation
by the manufacturer indicated that this condition could be
initiated in a limited subset of devices under specific conditions.
No patient injury or death related to this condition has been
reported so far. According to Cameron Health, the subset of devices
that may exhibit this unexpected reset state are those initially
shipped with software versions 2.1.135 or earlier and subsequently
upgraded to version 2.3.308. Cameron Health records indicate that
up to 323 devices worldwide could meet these criteria. No devices
implanted after March 2011 are affected. A programmer software
update (version 1.90.0) is available to eliminate the possibility
of this unexpected reset state occurring. While the DH is following
up with the manufacturer on the supply of the device in Hong Kong,
a spokesman urges patients who might have the affected device
implanted to contact their physicians immediately should they
notice an audible tone emitted from the device or should they have
any queries. The Department has alerted the Hospital Authority,
private hospitals, relevant institutions and medical associations
to the advisory. While the DH has not received any adverse report
so far, the department will maintain vigilance and monitor the
development of the issue.